Dear Linda:
I use marker training and have gotten Ed's marker training video, loved it.
I also do some marker training with all my dogs together. I usually do the review, or warm up with all my dogs, and then have taught them it is the others turn.. they have to wait. For new behavior I put the others away and take each dog and train them individually until they get it consistently, then I add the other dogs. My one dog terra, has learned to speak watching Cody speak. So they do learn from one another.
My dogs bindi and cody like the competition of who can get to their mat the quickest. Bindi and cody take turns on the treadmill, and while one is on the treadmill,the others waits, and I review their hand signals. (So they don't get confused. I reward them as they work on the treadmill.) Bindi is rock solid, Cody gets so excited he sometimes is his own worst enemy in training. Terra is new and she is the kinda of dog, very smart, but wants it her way, she will sit "next to the mat" and try and get me to giver her a reward, she gets ignored. When she sees this won't work, she immediately lays down on her mat. So they all are different. I try and make it fun, and whatever I am training them, I try and make it a part of their day each day, I incorporate it in their lives so they are always reviewing.
Hope this helps.
May God bless you, Oh, I take what is good from the positive methods, but agree with Ed, my dogs anyway, have to have corrections, a pack leader of wolves would correct its pack, so, I correct mine.
Have fun!